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OUTLINE

I. GLOSSO-PHARYNGEAL NERVEII. HITCHHIKING FIBERS

CRANIAL NERVES II: BRANCHES OF IX

IX - GLOSSO-PHARYNGEAL

- review branches of IX- pathways complicated by hitch-hiking fibers

IX

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VII, IX and X are complex and have a number of components

CRANIAL NERVE CHART: TYPES OF NEURONS

X

Branchialmuscles Autonomic

SomaticSensory

VisceralSensory

Taste,Smell

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SVE - Special Visceral Efferents - Branchial Muscles

- motor to voluntary skeletal muscles derived from branchial arches- visceral because develop in pharynx then migrate

Second - Facial VII

ThirdGlosso-pharyngeal IX

First -TrigeminalV

FourthVagusX

SixthAccessoryXI

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CRANIAL NERVES I. GVE PARASYMPATHETIC GANGLIA

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GSA - General Somatic Afferentssensory to skin, ORAL cavity, NASAL cavity, joints, muscles

ALMOST ALLTRIGEMINAL VEXCEPTION:SKIN OF OUTER EARALSO1) VII- FACIAL2) IX - GLOSSO-PHARYNGEAL3) X - VAGUS

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GVA - General Visceral Afferents

Nasal CavityGSA

Oral CavityGSA

Sensory to Pharynx and derivatives

All Pharynx is GVAIn 3 Cranial Nerves

NASOPHARYNX - VII

OROPHARYNX - IX

LARYNGOPHARYNX - X

IX – Also provides GVA touch to post. 1/3 of tongue

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SVA - Special Visceral AfferentsChemical Sense - TASTE - in three cranial nerves

X - VAGUS -ant. to epiglottis

IX - GLOSSO-PHARYNGEALpost. 1/3 of tongue

VII - FACIAL -ant. 2/3 of tongue

TONGUE

IX - SVA taste andGVA touch to post. tongue

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CN XII Receives hitchhiking fibers from C1

BRANCHES OF IX HITCHHIKE WITH BRANCHES OF V

Trigeminal V Receives hitchhiking fibers from Facial VII and Glossopharyngeal IX

VIIChordaTympani

V3 Lingual

example:

Parasympathetics from IX also hitchhike with a branch of Trigeminal: Auriculotemporal nerve (V3)

Recall: Recall:

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PARASYMPATHETICS AND TASTE FIBERS OF VII AND IX JOIN BRANCHES OF V

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IX

IX - GLOSSOPHARYNGEAL

leaves Post. Cranial fossa via Jugular Foramen

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LesserPetrosal N.

exits viaJugular Foramen

1. Tympanic NerveForms tympanic plexus; GVA sensory to middle earMastoid sinusauditory tube

2. Lesser PetrosalGVE parasympTo Parotid Gland

Tympanic N.

IX

IX - GLOSSOPHARYNGEALNOSE

exits viaJugular Foramen

Auditorytube

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IX Lesser Petrosal –synapse in Otic GanglionPost. ganglionic parasymp. from Otic ganglion join Auriculo temporal N. V 3 -to Parotid Gland

May also carry GSA fibers to outer ear

Lesser Petrosal N.

AuriculoTemporalN. V 3

IX- LESSER PETROSAL NERVE - PAROTID GLAND

Parotid Gland

Otic Ganglion

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3. Carotid branchesSensory – Carotid sinus - blood PressureCarotid Body - CO2 in blood

4. Motor Nerve to Stylopharyngeus

5. Pharyngeal BranchesSensory to oropharynx

6. Tonsillar BranchesSensory to palatine tonsil

7. Lingual branchesSensory (touch) & taste to post. 1/3 of tongue

Tonsillar

Lingual

Pharyngeal br

Carotid

Tympanic

IX - GLOSSOPHARYNGEALMotor Nerve to Stylopharyngeus

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PARASYMPATHETIC OF IX JOIN BRANCHES OF V

AURICULO-TEMPORALNERVE

IX – LESSERPETROSAL – OTICGANGLION

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INTEGRATION REVIEW

IX –CENTRAL LESIONS –Nucleus solitarius - GVA-- 9,10: cardiac-pulmonary areflexia; loss of chemo-baro-sensory afferents in the carotid sinus/body (Carotid branch IX)

IX – GAG REFLEX IN - IX (PharyngealSensory branches) OUT - X

Carotid

Pharyngeal branches

GAG REFLEX